The present invention relates, in general, to vision optical systems and, more particularly, to illumination devices for imaging optics.
Machine vision optical systems are employed to obtain a digital image of an object in the field of view of the optical system for analysis. In order to accurately image the object, so as to be able to determine if the object has any surface defects, or to determine the dimensions of the object, illumination is typically required.
Previously, illumination devices in the form of a ring of illuminatable segments, such as light bulbs, LEDs, have been mounted in a ring shaped holder encircling the lens of the camera. This illumination device projects light onto an object spaced from the lens so as to provide sufficient illumination for the lens to obtain an accurate image of the object. Controls to vary the intensity or number of LEDs that are illuminated are known.
However, since machine vision optics are used with objects having a wide range of size, shapes and surface topography, it is still desirable to have an adjustable illumination source which can be positioned to provide adequate illumination onto any point on an object as well as be able to provide illumination to a wide range of object sizes and surface topographies.